#StrataBuddy-mainmenu {
  list-style-image: url("chrome://StrataBuddy/skin/images/app-tab5.png")!important;
  -moz-image-region: rect(0 77px 23px 0) !important;
  margin: -1px -3px 0 -3px !important;
}

#StrataBuddy-mainmenu:hover {
  -moz-image-region: rect(23px 77px 46px 0) !important;
}

#StrataBuddy-mainmenu[open="true"] {
  -moz-image-region: rect(46px 77px 69px 0) !important;
}